（1 北京工业大学建筑工程学院， 北京100124； 2 北京万兴建筑集团有限公司， 北京102600）

［摘要］北京市亦庄移动硅谷创新中心项目2号、3号楼，地上25层，结构高度101.70m，在24层、93.70m高以上为长悬挑现浇混凝土结构，该悬挑结构施工需要具有足够刚度和承载力的支撑平台。提出了一种以主体结构型钢混凝土柱为支点的高空大悬挑主桁架式钢模架，进行了1：3缩尺模型的受力性能试验研究，分析了承载力、刚度、屈服机制及损伤演化过程，利用SAP 2000软件进行了受力全过程数值模拟，施工过程中进行了现场监测。结果表明：该平台采用主桁架式结构体系，受力合理，具有足够的刚度和承载力；主体结构型钢混凝土柱与主桁架连接节点工作可靠；数值模拟所得荷载-位移曲线与试验结果符合较好；由试验结果按模型律所得原型的最大挠度与现场实测最大挠度符合较好。

［关键词］高空大悬挑；主桁架式；钢模架；受力性能；试验研究

中图分类号：TU323-4文献标识码：A文章编号：1002-848X(2021)09-0120-08

Experimental study on mechanical behavior of main truss steel formwork of high-altitude large cantilever

CAO Wanlin1, ZHANG Yuan1, BIAN Jinliang1, LIU Ping1, LI Jinshui2, GAO Teng2

（1 College of Architecture and Civil Engineering, Beijing University of Technology, Beijing 100124, China；2 Beijing Wanxing Building Group, Beijing 102600, China）

Abstract:Mobile Silicon Valley Innovation Center Project is located in Yizhuang, Beijing. Building 2 and 3 have 25 floors above ground which are 101.70 meters high. Long cantilever cast-in-place concrete structures are constructed on the 24th floor and above the height of 93.70m. The construction of the cantilever structure requires a supporting platform with sufficient stiffness and bearing capacity. A high-altitude large cantilever main truss steel formwork with the main structural steel concrete column as the fulcrum was proposed. A model mechanical performance test study of its 1:3 scale ratio was completed. The bearing capacity, stiffness, yield mechanism and damage evolution process were analyzed. SAP 2000 software was used to simulate the whole process of force. On-site monitoring was carried out during the construction process. The results show that the platform which adopts the main truss structure system has reasonable force, sufficient stiffness and bearing capacity. The main structural steel reinforced concrete column and the main truss connection joint work reliably. The load-displacement curves obtained by numerical simulation are in good agreement with the test results. According to the test results, the maximum deflection of the prototype obtained by the model law is in good agreement with the maximum deflection of the field.

Keywords:high-altitude large cantilever; main truss; steel formwork; mechanical performance; experimental study

*国家自然科学基金资助项目（51578020）。

作者简介：曹万林，博士，教授，博士生导师，Email: caowl@bjut.edu.cn。